Circular slider for slide fastener



Aug. 4, 1970 A. FROHLICH 3,522,639

CIRCULAR SLIDER FOR SLIDE FASTENER Filed INVENTOR: FPOHLICH s {Km-El TM,4 TTORNEY United States Patent Ofioe 3,522,639 Patented Aug. 4, 19703,522,639 CIRCULAR SLIDER FOR SLIDE FASTENER Alfons Frohlich, Essen,Germany, assignor to Opti- Holding AG, Glarus, Switzerland, acorporation of Switzerland Filed Jan. 16, 1968, Ser. No. 698,226 Claimspriority, applicatiglgzrmany, Jan. 21, 1967,

Int. Cl. A44c i9/26, 19/32 US. Cl. 24205.15 3 Claims ABSTRACT OF THEDISCLOSURE bed linen and the like.

This application is a continuation-in-part of application Ser. No.651,757, filed July 7, 1967.

My present invention relates to slide-fastener closures and, moreparticularly, to an improved slider for such closures.

In the aforementioned copending application I have pointed out that awide variety of sliders for opening and closing slide-fastenerassemblies, upon movement of the slider to and fro along the couplingelements, are known. In general, such sliders are somewhat elongated inthe direction of movement and have relatively wide mouth portions intowhich the separable coupling elements are fed as Well as a somewhat morenarrow tail portion from which the interfitted coupling elements emerge.The upper and lower plates of the slider, because of theirconfigurations and outlines, are frequently referred to as upper andlower shields and that designation is used from time to timehereinafter. The upper and lower members or shields may be integral withone another or interconnected by wdgelike webs bridging the shields anddefining the channels within the slider. In some constructions, theslider is assembled by joining the individual shields together with aseparate web member or bridge piece, or by mounting one of the shieldsupon the bridge piece which is formed unitarily with or is previouslyaflixed to the other shield. One or both of these sheet-metal shieldmembers is generally provided with relatively thin inwardly turnedaprons, formations or edges of the thickness of the sheet metal designedto co-operate with the web member to delimit the outer sides of theaforementioned guide channels. As pointed out in that application,sliders of this type have not, for the most part, been capable of withstanding fabric-handlin g treatments involving rigorous a gitation offabrics carrying the slider or compression of the fabric between rollersor the like. Such slide-fastener assemblies are not considered to bereadily ironable by hand, by platen-type ironing apparatus or byheatedroller mangles. With slide-fastener assemblies prior to thedevelopment described in the copending application, such fabric-handlingtreatments frequently caused tearing in the region of the slider ordamaged the slider by distorting it and partially closing its guidechannels, thereby preventing the slider from being drawn along thecoupling elements of the stringer tape. This disadvantage was found tobe especially significant when the slide-fastener assembly was used withwashable fabrics and garments. While many suggestions have been made tolimit the number of projecting corners and shape edges of the slider,and the coupling elements have themselves been made capable ofwithstanding ironing or washing by substituting continuous coils ofsynthetic-resin filament for the spacedapart metallic coupling elements,there had not been (prior to the development described in theaforementioned copending application) any successful suggestion as tohow to preclude closing of the channels and jamming of the slidefastener. It will be recognized that the relatively elongatedconfiguration of prior-art sliders, in which the web connecting theupper and lower shields was located at one end of the slider, made itparticularly easy to press the cantilevered tail portion together anddistort the slider and the shapes of the channels.

These disadvantages of earlier systems were obviated in the system of myprior application by providing an improved slider for opening andclosing (i.e. disconnecting and interconnecting) interleavable couplingelements of a slide-fastener stringer, in the form of a pair ofgenerally disk-shaped upper and lower shield members interconnected andunitarily formed with a wedge-shaped web bridging these members, themembers having circular configuration and registering substantiallycoextensively to impart to the entire slider a circular outline and agenerally flattened character. The upper and lower shield members of theimproved slider were curved away from one another, i.e. outwardly convexand of lenslike configuration, with the greatest slider thickness inline with the web or bridge member. The slider was molded from asynthetic resin with the upper and lower shield membens having bulgingouter surfaces free from discontinuities and conforming to surfaces ofrevolution or being axially symmetrical with respective centrums alignedwith one another and disposed along an axis of the slider traversing theregion of maximum thickness thereof and passing through the web. Theupper and lower circular and coextensive shield members were providedwith inwardly turned rims having formations of rounded edgeconfiguration defining, With the wedge-shaped bridge member, therespective channels; a pair of ridges were disposed centrally along theinner surfaces of the upper and lower shield members and tapered awayfrom the wedge member, while merging therewith, to form central guidesseparating the channels from one another. The formations were twoprojections from one of the shield members, angularly offset from oneanother and spaced from the Wedge member about the center of the disksso as to define with the flanks of the web member generally divergentchannels with parallel walls to guide the coupling elements at theappropriate fastener-opening angle. The wedge member, moreover, whenconsidered in cross section at a plane parallel to the shield members,formed an equilateral triangle whose altitude generally approximated theradius of the shield member and had a thickness along this altitude ofabout %R to 1R. The lateral guide formations were of substantialthickness, i.e. thicknesses ranging from 0.1R to 0.5R (where)R is theradius of the disk or shield), thereby permitting these formations toact as abutments withstanding excessive compression of the shieldmember's transversely to one another. In this case, the formations actednot only as guide elements but also as walls which closed the sides ofthe circular slider and as abutments preventing excessive compression ofthe shield members in the transverse direction. The distance betweenthese formations and the opposing shield member, with which they wereengageable upon compression, advantageously was less than the degree ofcompaction of the slider permissible'without detrimental permanentdeformation of the coupling elements received within the slider.

It is the principal object of the present invention to provide a sliderfor a slide-fastener closure which extends the principles originally setforth in the aforementioned copending application and to thereby providea slider which allows the closure to be ironed by hand or machine.

A further object of this invention is to provide a slider, of animproved and somewhat simpler construction by contrast with that claimedin the aforementioned copending application, which enables theslide-fastener assembly to be subjected to heated-roller ironing,rigorous washing, etc. without distortion of the slider, the couplingelements passing therethrough on the fabric on which the slide fasteneris mounted.

I have now found, as a further development of the principle set forth inmy copending application Ser. No. 651,757, that a slider fulfillingthese objects, has, in addition to an upper member, a lower member and awedge or bridge member interconnecting the upper and lower members anddefining a pair of guide channels diverging at the wedge member andmerging toward the tail of the slider diametrically opposite the wedgemember, a pair of lateral guide elements or aprons which extenddownwardly from the upper shield member in spaced relation to the lowershield member but to flank the latter so that a pair of slots are formedalong the channel between the lateral guide formations or aprons and thegenerally Y-shaped lower member which is disposed between these aprons.The slide-fastener stringer, upon its passage through the channels,extends through the slots on opposite sides of the interconnectablecoupling elements to impart an S-like configuration to theslide-fastener halves adjacent the coupling elements and on both sidesthereof. The lateral aprons or formations, which can be considered to becantilevered from the upper shield member and to overhang the lowershield member, reach downwardly substantially to the plane of the bottomsurface of the lower member and conform, in outline to the circularconfiguration mentioned earlier in connection with my copendingapplication.

According to another important feature of this invention, the slider hasa circular outline and a thickness at three equispaced locations equalto or a substantial fraction of the radius of the slider, the threeequispaced locations being offset from one another about the axis of theslider and its center, e.g. by 120". The three supporting locations, atwhich the thickness of the slider is equal to the height of thesupports, correspond to the downwardly extending formations mentionedearlier and the wedgeshaped bridge piece which, together with theformations, defines the channels for the coupling elements. As in theaforementioned copending application, the downwardly extending aprons orformations perform a number of functions. They have minimum radialthicknesses equal to a substantial fraction of the radius of the slider(e.g. from 0.1 R to 0.5=R where 'R is the radius of the circular outlineof the slider); the radial thickness of the web may range between %R and1R.

The heights of the formations, which also constitute the lateral guidesfor the channels, is equal to the thickness of the slider so that theseformations act as abutments similar to the web or bridge piece and thusprevent any compression of the slider by the heated mangle roller duringironing. According to a preferred construction, the lateral guideformations are formed on a slider which is flattened, i.e. has its upperand lower surfaces lying in parallel planes spaced apart by thethickness of the slider and the height of the aprons or formations. Itshould be noted, however, that a convex upper surface may be provided asdescribed in the aforementioned copending application in which case theapex of the convexity should be located over the centrum of the web orbridge piece. It will be evident that this system has the advantage thatthe slider of the present invention is totally resistant to deformationand compression during ironing and can withstand considerable axialpressure without noticeable deformation. The lateral guide formations,which are of augmented thickness and flank the lower shield member,

form a reinforcing couple nondeformable by mangle pressure. The slidercan be composed of die-cast metal or injection-molded synthetic resin.

While preferably the slots extending along the guide channels aregenerally upright, that is force the fabric of the support tapes of thestringer to lie generally parallel to the axis of the slider andperpendicular to the boundary planes mentioned earlier, it has beenfound that, for bed linen and other materials which do not requireconstant use of the slide fastener, advantage is gained by shaping theslot so that less force is required to shift the slider. To this end,the guide formations may have rounded edges or outwardly divergentflanks.

The above and other objects, features and advantages of the presentinvention will become more readily apparent from the followingdescription, reference being made to the accompanying drawing in which:

FIG. 1 is a front view of a slider embodying the present invention;

FIG. 2 is a cross-sectional view taken along the line IIII of FIG. 1;

FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 1;and

FIG. 4 is a view similar to FIG. 1 of another embodiment of the presentinvention.

In the drawing, i.e. in FIGS. 13 and 4, I show a pair of sliders whichare particularly convenient for use with bed linen and other materialswith which the slider is not used too frequently but which may besubjected to ironing in a heated-roller mangle or the like.

In FIGS. 1-3, I show a slider which, in its basic construction,comprises a circular upper shield member 2 unitarily and integrallyformed in monolithic fashion with a Y-shaped tongue 3 parallel theretoand transversely spaced therefrom, the tongue 3 forming the lower shieldmember. The upper and lower shield members 2 and 3 are bounded by upperand lower planes P and P which are spaced apart by a distance d, theirsurfaces being planar. The upper and lower members are alsomonolithically molded with a wedge-shaped web or bridge member 4 whichforms a coupling-element separator of triangular cross section. A pairof guide channels 6, 6a and 6b are formed in the slider between a pairof downwardly extending aprons in the form of abutment or supportformations 5 whose radial thicknesses t are equal at least to 0.1 to0.5R and may exceed this value depending upon the type of couplingelements used in the slide fastener, here represented at 1. The slidefastener comprises a pair of support tapes 7 formed at theirinterengageable edges with generally helicoidal coupling elements 1a and1b of nylon-type polyamide. The formations 5 are angularly spaced aboutthe center C of the slider from one another and from the bridge member 4from which the flat tongue 3 projects. A pair of parallel upright flanks5a and 5b of the formations 5 form the channel 6 at the tail of theslider diametrically opposite the bridge piece 4 while divergent flanks5a and 5b, respectively parallel to the divergent flanks 4a and 4b ofthe bridge piece establish the branches 6a and 6b of the channel and themouth of the slider. Along the channel 6, 6a and 6b, a pair of slots 6'and 6" are defined by the flanks 5a, 5a and 5b, 5b and the opposingedges 3a and 3b of the lower shield member 3. As can be seen from FIG.1, the underside of the lower shield member 3 lies in the plane P atwhich the formations 5 terminate, these formations being spaced from theedges 3a and 3b by a distance sufiicient to clear the fabric webs 7 ofthe stringer.

In the modification of FIG. 4, the surfaces 15a and 15b corresponding tosurfaces 511 and 5b slope gradually outwardly while the edges 13a and13b of the tongue 13 are outwardly tapered and rounded to permitsmoother movement of the slider along the stringer. In both cases,however, as the webs 7 pass through the channels 6, 6a and 6b, on bothsides of a longitudinally median plane M, the web is deformed intoS-shaped configuration within the slider. The overall thickness d of theslider is equal to or a major fraction of the radius R while thethickness of the upper shield member is also a major fraction of theradius R of the slider, which has a circular outline. It will be evidentthat axial pressures as represented by the arrows p (FIG. 3) can befully absorbed by the slider without deformation thereof.

Channel 6, forming part of the branched guide path 6, 6a, 6b for the twofastener halves 1a and 1b, is of inverted-U shape as best seen in FIG.1, this shape being less pronounced but still discernible in themodification of FIG. 4. The upper surface of tongue 3 (or 13), extendingalong the bight of the U, is broad enough to support the interlinkedfastener halves 1a, 1b in a coplanar position within the channel 6.

I claim:

1. In a slide-fastener assembly comprising a pair of flexible stringertapes, a pair of interengageable fastener halves carried by said tapesin juxtaposed relationship, and a slider reciprocable along saidjuxtaposed fastener halves for alternately interlocking and disengagingsame, the improvement wherein said slider comprises a flat, disk-shapedbody with a downwardly open, generally Y-shaped guide path for saidfastener halves defined by a central bridge piece and a pair of flankingformations integrally depending from said body, said slider furtherincluding a tongue integral with said bridge piece and held thereby inspaced-apart relationship With said body to form a substantiallyY-shaped fastener-supporting shelf at the bottom of said guide pathseparated by two narrow gaps from said flanking formations, theundersurfaces of said tongue and formations being substantiallycoplanar, said shelf having a stem in a common channel of said guidepath and a pair of arms in two branch channels of said guide path, saidcommon channel having a cross-section generally of inverted-U shape withthe bight of the U defined by the upper surface of said stem, said uppersurface being substantially flat and wide enough to support aninterlocked section of said fastener 'halves in substantially coplanar.relationship together References Cited UNITED STATES PATENTS D. 114,2694/1939 Pouy.

2,068,939 1/ 1937 Winterhalter. 2,120,924 6/1938 StillSChWeig 24205.12,189,727 2/ 1940 Corner 24-205.14 3,115,689 12/1963 Jacobs 24205.15 X

FOREIGN PATENTS 10/1965 Switzerland. 12/1940 France.

BERNARD A. GELAK, Primary Examiner US. Cl. X.R. 24-2051

